When creating a model of a nonlinear electrical system based on differential equations, it is important to keep in mind that ordinary differentiation does not give an adequate mathematical idea of ​​the nonlinear physical processes taking place. Even in the simplest case of a conductor with a current, the construction of an adequate model is only possible if the tensor approach is applied. From this point of view, any electrical system is an object of tensor methodology. A typical example of a non-linear electrical system is an AC electromagnetic drive. The nonlinear nature of the processes in such devices is due to a number of reasons. The main reasons are: current displacement in the winding of the AC electromagnetic drive and saturation of the steel of the magnetic circuit in the process of magnetization. Both phenomena admit tensor description, which is confirmed by the research presented in the article.

Keywords: dynamic characteristic of magnetization, electromagnet, mathematical model, tensor methodology

This article presents an algorithm for predicting and avoiding an obstacle with a single UAV. The proposed method is an extended version of the previous work with the additional collision avoidance capabilities which are based on the building of a bypass curve. In this work, the authors proposed a method for generating trajectories, which uses Bezier curves with the properties of the Pythagorean Hodograph.

Keywords: unmanned aerial vehicle, Bernstein-Bezier polynomials, Pythagorean Hodograph, trajectory generation, obstacle avoidance, programmed motion

This article discusses one of the parts of the development of a device for testing samples of magnetostrictive materials. A study of various designs and an analysis of the sensitivity of the measuring system are presented. The substantiation of the use of a magnetic shunt to increase the sensitivity is given, which is confirmed in field experiments.

Keywords: magnetostrictive materials, basic magnetization curve, magnetic shunt, magnetic flux

Stochastic systems are systems in which changes are random. In which the predicted values depend on a probability distribution. An example of a stochastic system in a power system, the operation of which is affected by many random factors, their analysis and control will allow you to control the safe cycle and reliability of operation. Currently, there are methods and mathematical tools that allow us to estimate the likelihood of any phenomenon and situation with acceptable accuracy, however, they are practically not used to solve this problem on electrified railway transport. Therefore, the work summarizes the existing methods of probabilistic forecasting, and gives recommendations on their application to solve the existing problematic of the issue. Further, the paper shows a method for determining the probability of failure of a constituent structural element of any, arbitrarily complex, stochastic system, to which the contact network of electrified railways belongs. In the conclusion of the work, an elementary method-oriented software tool with the functional purpose of automating statistical methods for solving problems of primary data processing and calculating elementary statistics in the process of risk management is proposed, as well as loading and maintaining a database that is subsequently oriented to the principles of machine learning.

Keywords: electrified railways, stochastic systems, operational reliability, probability of failure, forecasting

The article discusses the main stages of identification of a control system for maintaining a given temperature, which includes an actuator, a control object and a temperature sensor. The initial data were experimental values ​​obtained under various setting influences on objects of the material world. To confirm the accuracy of the calculations and the selected methods for identifying parameters, mathematical modeling of the system in the Matlab / Simulink package is presented. At the end of the article, quantitative and qualitative assessments of the obtained mathematical models are given. The identification of the parameters of the control system for maintaining the set temperature was successful. The developed algorithm for describing material objects by mathematical models showed a low error, which indicates the applicability of this approach in real technological processes of production management.

Keywords: identification, mathematical model, control object, control system, transient response, full-scale experiment, transfer function

The modeling heavy metal transfer by the ground source to the lower boundaries of the soil is considered. The transfer process is described by a system of equations included the Navier-Stokes equation, the k-ε model and the nonstationary diffusion equation. The initial and boundary conditions are given at the boundaries of the air and liquid in the soil flow, also in the air-ground contact zone, which are necessary for solving the boundary value problem. The results of numerical simulation obtained using the ANSYS fluent program are shown. The result analysis is based on the comparison of numerical modelling and long-term observations data around the hydroelectric power plant.

Keywords: k-ε model, diffusion equation, numerical modelling, ANSYS, Novocherkasskiy hydroelectric power plant

The paper considers mathematical models obtained on the basis of experimental studies of electrical sheet steel. The models reflect the error in determining the main magnetization curve of electrical steel. The magnetic properties are determined in the center and at the edge of the cut of sheet samples with a size of 150 × 150 mm, made by cutting with guillotine shears and laser cutting. The choice of scale factors for calculating the main magnetization curve with an error of ± 5% according to the measured Weber-ampere characteristic has been substantiated. The study was carried out using a device for express control of the magnetic characteristics of electrical sheet steel. The main curve of magnetization of the sample material from sheet electrical steel was determined in an alternating magnetic field with a frequency of 50 Hz, along the direction of rolling. Investigated samples of isotropic sheet electrical steel grade 2212.

Keywords: mathematical model, electrical steel, magnetic properties, magnetization curve

Stable reliability characteristics are a guarantee of non-emergency operation of electrified railways, undoubtedly, the profitability of transportation processes is growing. The article proposes an innovative method for determining the characteristics of reliability, with a decrease in the risk of failure or emergency. Electric traction used in most of the railroad landfill. It is necessary to consider the issues of reliability of the power supply system to predict the state of the system and study the patterns of interaction that affect system and non-system communications. Therefore, we will pay special attention to the reliability of the power supply system; in order to predict failures, first of all, it is necessary to know the patterns of interaction and patterns that affect system and non-system communications. The danger of risk directly depends on the number and duration of failures. In the power supply system, a huge number of heterogeneous and differently distributed objects, nodes and elements operate in different modes and are susceptible to different operational influences.Therefore, the work summarizes the existing methods of probabilistic forecasting, and gives recommendations on their application to solve the existing problematic of the issue. Further, the paper shows a method for determining the probability of failure of a constituent structural element of any, arbitrarily complex, stochastic system, to which the contact network of electrified railways belongs. In the conclusion of the work, an elementary method-oriented software tool with the functional purpose of automating statistical methods for solving problems of primary data processing and calculating elementary statistics in the process of risk management is proposed, as well as loading and maintaining a database that is subsequently oriented to the principles of machine learning.

Keywords: electrified railways, predictive analysis, operational reliability, probability of failure, forecasting

This article provides information that there are different categories of users with different groups of behavioral features. All this data is separated from each other. In the course of this work, it was found that if all data on user models are combined into one method, then the analysis by which information about a virtual person is obtained can lead to improved adaptability of web resources using new technologies.

Keywords: usability, virtual reality, types of virtual personalities, segmentation, socialization, user, Internet

This paper proposes an algorithm for automatic segmentation of subretinal fluids in the macular retinal layers of the retina. The proposed algorithm is implemented in an integrated development environment - PyCharm, a high-level general-purpose programming language (GPL) - Python was chosen. The proposed algorithm together with other methods of analysis of morphometric parameters of the human retina, which are still under development, will be used for more accurate diagnosis of the stage and degree of retinal damage in age-related macular degeneration.

Keywords: software, image processing, diagnostics, automatic segmentation, macula, retina, age-related macular degeneration, optical coherence tomography

The article considers a model for evaluating the performance indicators of information resource exchange in corporate systems, designed to analyze the ability of systems with a distributed registry to ensure the timeliness and completeness of information exchange. As the main indicator, it is proposed to take into account the probability of failure of a segment of the corporate system for each epoch. To find this indicator, we use probabilistic estimates of sums bounded from above by hypergeometric and binomial distributions with probability boundaries of Chebyshev, Heffding, and Schwatal. A numerical and comparative analysis of the proposed estimates is carried out.

Keywords: distributed registry technology, information system, segmentation, block chain

The implantation of electrodes on the skull of mice requires precise positioning. For these purposes, it is necessary to create a coordinate system that rests on the cranial sutures. The aim of the work is to train a model based on convolutional neural networks. The model should automatically draw the seam line. Investigating this issue, a method for solving the problem of seam approximation based on U-net is proposed. This study faces the difficult problem of accurately locating the cranial suture. As part of the study, a structure similar to U-net was developed and thought out. The results of the work will allow biologists to perform more accurate stereotaxic operations, by inserting electrodes into a more precise position, to receive certain signals from the brain, in order to record changes when various aromas are applied to the mouse receptors.

Keywords: convolutional neural network (CNN), seam approximation, fully convolutional network (FCN), deep learning, semantic segmentation, object segmentation, neural network, computer vision, biomedical image, machine learning, image processing

In this article, the actual topic of project activities in the framework of the modernization of higher education in Cambodia. In this article, we analyzed the situation due to which among recent university graduates there is a shortage of highly qualified personnel in such areas as agriculture, exact sciences, mechanical engineering and manufacturing. We also studied information about the largest university in the country - Queen Phnom Penh University.

Keywords: higher education, modernization, innovation, Cambodia, Russia

The article discusses the methodology for ensuring the timeliness and completeness of the exchange of information resources in corporate networks built on the basis of distributed registry technology, which takes into account the variability of the strategy of the behavior of the distributed registry system during information exchange. The technique takes into account non-standard functions, such as the formation of a branch of the processed data and the impact of an attacker, and also allows you to determine the average value of the block generation delay time by adjusting the number of operations required to solve the block. The use of this method allows to increase the value of the indicator of timeliness and completeness of the exchange of information resources in the corporate network by 30% compared to the existing system of information exchange.

Keywords: distributed registry technology, corporate network, information resources

The article deals with the difference model of coordination of general and private interests in the distribution of resources in marketing networks. The dynamics of a managed system describes the interaction of members of the target audience (base agents), leading to a change in their opinions (spending on the purchase of goods and services of firms competing in a certain market). The gain of each firm includes two components: the total opinion of the base agents, taking into account marketing costs (the common interest for all agents of influence) and the return on investment in some private activity. The Coordinating Center determines the marketing budgets of the firms and maximizes the total opinion of the base agents, taking into account the resources allocated to the firms. The total discounted income of the Center and the agents of influence are found. The results are analyzed and the optimal allocation of resources is concluded.

Keywords: models of coordination of public and private interests, simulation, modeling, marketing, resource allocation, budget, private activity

A method for measuring the magnetic characteristics of high-coercive permanent magnets made of rare-earth materials, such as neodymium-iron-boron and samarium-cobalt, is proposed. The essence of the method is as follows: the data on the measured supply voltage and the characteristics of the magnetizing installation base a mathematical model; the measured shape of the magnetizing current pulse is fed into the mathematical model and compared with the simulated current pulse in the comparison device; further, if the difference in current characteristics does not satisfy the measurement accuracy, then adjustments are made to the mathematical model. Thus, the mathematical model determines the magnetic characteristics of a permanent high-coercive magnet. The method is developed based on full-scale model tests using a multiphysical computer model. The implementation of the measurement method is based on modern IT solutions, the multiphysical model is built in the COMSOL Multiphysics software package.

Keywords: magnet, magnetic parameter, multiphysical model, magnetization, highly coercive material, neodymium, wavelet, Fourier analysis, COMSOL

The article considers the issue of measuring and controlling the parameters of a high-voltage AC circuit using a Bragg grid. A model of a fiber-optic sensor based on the magnetostriction effect, the main component of which is a fiber-Bragg grating, is proposed. The 3D modeling of the magnetostriction process and the design of the block diagram are carried out.

Keywords: optical fiber, magnetostriction, bragg grid, AC, sensor, solenoid, coil, nickel, ferrite, MathCAD, COMSOL

The method of compaction of subsident soils by deep explosions is widely used in civil construction of buildings and structures. It is characterized by high efficiency of soil compaction and low financial costs for the production of works. This emphasizes the undoubted advantage of the method in comparison with other analogues. In this paper, some features of constructing a mathematical model of compaction of subsident soils by deep explosions are described. The conditions for the existence and uniqueness of the solution of boundary value problems in the framework of the investigated model are given.

Keywords: subsidence soil, loess, deep explosion, concentrated charge, elongated charge, soil compaction, mathematical model, diffusion equation, boundary value problem, solvability of the model

The article is devoted to the study of administrative corruption in the model of combining general and private interests, taking into account the costs of controlling agents. As the subject of research, we considered mathematical models of a combination of general and private interests of a hierarchical structure such as "Principal-Agent" and "Supervisor-Agent". The administrative control mechanism was investigated for the case where the principal sets a lower constraint.

Keywords: models of the combination of general and private interests, corruption, resource allocation, hierarchical systems, management systems, the Germeier-Vatel idea, private and common interests, principal, agent, center, administrative mechanism

This article proposes the development of a method for transmitting secure messages using a combination of best practices for organizing data exchange and cryptographic instant messaging protocols using end-to-end encryption. It considers ways of organizing an application using a peer-to-peer network and client-server architecture. It analyzes popular instant messaging protocols using end-to-end encryption. The software components of the application based on the developed method are described.

Keywords: messenger, end-to-end encryption, cryptographic protocol, instant messaging, peer-to-peer network, client-server

The paper presents a formalized statement of the problem for conducting a comparative analysis of the efficiency of distributed information processing systems. Reliability, technical-operational and technical-economic indicators of the distributed information processing systems functioning were selected as the main efficiency criteria. At the conceptual level, this problem was reduced to the problem of vector optimization, the solution of which is associated with significant difficulties. An alternative approach to solving this problem is proposed.

Keywords: distributed information processing system, vector optimization, availability factor, average system response time, fault tolerance coefficients, total downtime cost

This article briefly discusses recurrent neural networks and bidirectional recurrent neural networks. A conditional random field is also described. In particular, we consider the vector representation in the form of the ELMo model, the bidirectional language model and its fine-tuning. A diagram of the architecture of a bidirectional recurrent neural network with CRF is also given.

Keywords: named entity recognition, neural network, word vector representation, language model, conditional random field, neural network architecture, recurrent neural network, natural language processing, bidirectional recurrent neural network

Actuator drives are widely used both in consumer electronics and in industrial systems: as all kinds of locks, couplings; as part of valves that control the flow of liquids or gases; in robotics; alarm systems, etc. In the event of a failure of the actuator drive, it is not typical for it to restore the operating mode. As a consequence, predicting reliability plays an important role. The article discusses the development of a method for processing the weber-ampere characteristics of actuator drives. Weber-ampere characteristics are converted into ampere-weber ones, reflected by the maximum flux linkage value, and interpolated by the current values ​​that are the same for all characteristics. The characteristics obtained in this way are transformed by the method of principal components and are represented by a point in three-dimensional space. By the location of the points of the center of mass and the dispersion of the groups of characteristics of one electromagnetic drive, a forecast is made about its state by the time of the next check according to the regulations. This method was applied to the characteristics of 10 actuator drives, each of which was subjected to mechanical resistance during operation. The characteristics transferred into the space of the principal components forms a figure resembling a boomerang. The movement of points from the upper edge of the "boomerang" through the center to the lower edge reflects the deterioration of its working properties.

Keywords: prediction, reliability, actuator drive, weber-ampere characteristic, principal components, flux linkage, data processing, duty cycle, malfunction, Statistica, points cloud, performance data

This article discusses the features of using Euler angles in the process of determining the position of an object in space. The material presented here will help to study in detail the use of Euler angles when working with inertial navigation sensors and facilitate the understanding of the construction of systems using such devices. Today, such embedded automated systems are used in a wide variety of fields: in aircraft modeling, in medicine, military equipment, and agriculture, and the scale of their use is growing every year. Devices that track the position of the body in space are widely used in such systems as drones, mobile robots, remote-controlled manipulators. These devices can significantly reduce the need for human participation in heavy and dangerous work.

Keywords: Euler angles, accelerometer, gyroscope, magnetometer, object orientation, inertial navigation sensors, yaw, pitch, roll

This article discusses how to develop and configure a set of models to find anomalies in data. A structural diagram of a model ensemble and a flowchart of an algorithm for searching for anomalies in data are proposed. An increase in the accuracy of finding anomalies when using an ensemble of models is shown.

Keywords: anomaly, algorithm, model ensemble, accuracy, confusion matrix, data set, committee, clustering, console application, model